JP2017119825A - Method for producing block-copolymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a block-copolymer having a polymer block comprising a structural unit derived from an acrylic acid ester, and a polymer block comprising a lactone ring structure and a structural unit derived from a methacrylic acid ester.SOLUTION: A block-copolymer having a polymer block (A) comprising a structural unit derived from an acrylic acid ester, and a polymer block (B) comprising a lactone ring structure and a structural unit derived from a methacrylic acid ester is produced by a method comprising a polymerization step of polymerizing a nitroxide polymer (A1) including a nitroxide structure having an organic phosphorus unit, and a monomer (B1) comprising a methacrylic acid ester and a 2-hydroxymethyl acrylic acid monomer, on the terminus of the polymer block (A).SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester.

In recent years, transparent resins have been widely used in optical materials such as optical lenses, prisms, mirrors, optical disks, optical fibers, liquid crystal display sheets and films, and light guide plates.
As such a transparent resin, a thermoplastic resin such as an acrylic resin is used. In particular, an acrylic resin having a lactone ring structure in the main chain obtained by cyclization of a copolymer having a 2-hydroxymethyl acrylate unit and a methacrylic ester unit is excellent in transparency and heat resistance. Used in optical films and the like (Patent Documents 1 and 2).

However, since acrylic resins having a ring structure are generally hard and brittle, imparting flexibility has been studied. For example, Patent Document 3 discloses that methyl 2-hydroxymethyl acrylate is present in the presence of polybutyl acrylate. An acrylic resin having a lactone ring structure is described in which polybutyl acrylate, which is a flexible component, is mixed by polymerizing and methyl methacrylate and then cyclizing.
However, the acrylic resin obtained by the method described in Patent Document 3 is not a block copolymer having a polybutyl acrylate block, but only a mixture of acrylic resin and polybutyl acrylate. However, there is a problem that the flexibility of the resin varies, and the transparency necessary for optical applications is not sufficient.
Therefore, a method for producing a block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester has been demanded.

JP 2001-151814 A JP 2010-215708 A JP 2007-100044 A

An object of the present invention is to provide a method for producing a block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester. .
Another object of the present invention is to provide a production method capable of efficiently producing such a block copolymer.
Furthermore, the present invention provides a novel block copolymer having a polymer block containing a structural unit derived from an acrylate ester, and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester, and this block copolymer. It is an object to provide a film including the above.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have obtained structural units derived from acrylate esters (hereinafter referred to as “reaction units”) by reversible addition-fragmentation chain transfer (RAFT) polymerization, atom transfer radical polymerization (ATRP), and the like. A block polymer is formed by alternately polymerizing a polymer block containing “acrylate unit” (hereinafter the same in the same expression) and polymer block containing a lactone ring structure and a methacrylate unit. After that, I came up with a method for carrying out the cyclization reaction.
Specifically, as a method for producing a triblock copolymer in which a polymer block containing a lactone ring structure and a methacrylic acid ester unit is bonded to both sides of a polymer block containing an acrylate ester unit, 2-hydroxymethyl acrylate and methacrylic acid are used. Lactone cyclization reaction (step 4) through an acid ester polymerization step (step 1), an acrylic ester polymerization step (step 2) and a 2-hydroxymethyl acrylate ester and methyl methacrylate polymerization step (step 3) Inspired by how to implement.
However, in such a method, particularly when producing a block copolymer in which three or more blocks such as a triblock body are bonded, there are many production steps, and it is necessary to strictly adjust the reaction conditions.

  As a result of further intensive studies on a more efficient production method, the present inventors have used a specific nitroxide polymer having an organophosphorus unit in the polymerization of a nitroxide polymer and a 2-hydroxymethylacrylic acid monomer. It has been found that a lactone ring forming reaction can be carried out together with a polymerization reaction by polymerizing a methacrylic acid ester in the polymerization step.

That is, a nitroxide polymer (A1) having a nitroxide structure having an organic phosphorus unit at the end of a polymer block (A) containing an acrylate ester unit, a monomer (B1) containing a methacrylic acid ester and a 2-hydroxymethylacrylic acid monomer Surprisingly, in addition to the copolymerization of the nitroxide polymer (A1) and the monomer (B1), in addition to the copolymerization, methacrylate units and 2-hydroxymethylacrylic acid monomer units A lactone ring formation reaction can also be performed between the polymer block (A) containing an acrylate unit and a polymer block (B) containing a lactone ring structure and a methacrylic ester unit. A block copolymer having an efficiency It was found to be able to Ku production.
In addition to the above, the present inventors have obtained various new findings as will be described below, and have made further studies and completed the present invention.

That is, the present invention produces a block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylate ester. A method comprising: a nitroxide polymer (A1) having a nitroxide structure having an organic phosphorus unit at a terminal of a polymer block (A); and a monomer (B1) containing a methacrylic acid ester and a 2-hydroxymethylacrylic acid monomer. The present invention relates to a method for producing a block copolymer including a polymerization step for polymerization.
In this production method, the polymerization may be carried out in the presence of a thiol compound in the polymerization step.

  Further, the present invention has a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylic acid ester, and has a weight average molecular weight. The block copolymer which is 150,000 or more is also included. In addition, such a block copolymer may be manufactured by the manufacturing method.

  In such a block copolymer, the molecular weight distribution may be 3 or less, and the thermal decomposition temperature may be 300 ° C. or more.

  Furthermore, the present invention also includes a film containing the block copolymer (for example, an optical film such as a polarizer protective film), a polarizing plate provided with the film, and an image display device provided with the polarizing plate.

According to the present invention, a block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester can be provided.
Moreover, according to this invention, with formation of the block polymer which has a polymer block containing an acrylate unit and a block containing a methacrylic acid ester unit and a 2-hydroxymethylacrylic acid monomer unit, a methacrylic acid ester unit and 2- Since the cyclization reaction (dealcoholization reaction) can proceed between the hydroxymethylacrylic acid monomer units, such a block copolymer can be produced efficiently.
In particular, in the production of a polyblock copolymer such as a triblock copolymer (for example, (B)-(A)-(B), etc.), a multi-stage polymerization process including a polymerization process and a cyclization process for each block is performed. There is no need to pass through, and it can be produced efficiently and the polymerization time can be shortened.

Generally, when a dealcoholization reaction for forming a lactone ring structure occurs, the reaction temperature in the polymerization system rises or the reaction solution bumps due to the formation of alcohol, so the reaction conditions must be adjusted strictly (for example, reaction Temperature control etc.) is required.
On the other hand, in the production method of the present invention, methacrylic acid ester and 2-hydroxymethylacrylic acid monomer can be copolymerized and the lactone cyclization reaction can proceed, so that the dealcoholization reaction becomes mild, A rapid increase in reaction temperature and bumping of the reaction solution can be prevented, and strict adjustment of reaction conditions is not required, and stable polymerization can be easily performed.

  Furthermore, the present invention can provide a novel block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester. Such a novel block copolymer is a block copolymer having excellent physical properties (characteristics) such as excellent heat resistance and thermal stability, and is extremely useful in optical film applications and the like.

Hereinafter, the present invention will be described in detail.
The present invention is a method for producing a block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylate ester. is there.
The production method of the present invention comprises a monomer (B1) comprising a nitroxide polymer (A1) having a nitroxide structure having an organophosphorus unit at the end of a polymer block (A), a methacrylic acid ester and a 2-hydroxymethylacrylic acid monomer. And a polymerization step of polymerizing.

[Nitroxide polymer (A1)]
The nitroxide polymer (A1) has a nitroxide structure having an organophosphorus unit at the end of the polymer block (A) containing an acrylate unit.
The nitroxide polymer (A1) may have a nitroxide structure having an organic phosphorus unit at least at one end of the polymer block (A), but preferably has both ends of the polymer block (A).

In the polymer block (A), the acrylate unit is not particularly limited. For example, aliphatic acrylate [for example, acrylic acid alkyl ester (for example, acrylic acid C such as methyl acrylate, ethyl acrylate, butyl acrylate, etc.) _1-18 alkyl), etc.], alicyclic acrylate [e.g., acrylate acrylate ester (e.g., _C3-20 cycloalkyl acrylate such as cyclopropyl acrylate, cyclobutyl acrylate), crosslinked cyclic acrylate (e.g., isobornyl acrylate) and the like], aromatic acrylates [for example, acrylic acid aryl esters (e.g., phenyl acrylate, C _6-20 aryl such as acrylic acid o- tolyl) acrylic acid aralkyl ester (e.g., benzyl acrylate Acrylic acid C _6-10 aryl C _1-4 alkyl), acrylic acid phenoxyalkyl (e.g., structural units derived from an acrylic acid ester of acrylic acid phenoxy C _1-4 alkyl), etc.] or the like, such as phenoxyethyl acrylate is Can be mentioned.
The acrylic ester unit may be composed of one kind or two or more kinds.

From the viewpoint of improving flexibility, the acrylate unit preferably includes at least an alkyl acrylate unit, more preferably includes at least a C _1-18 alkyl acrylate unit, and an n-butyl acrylate unit. It is more preferable that at least be included.

  In the polymer block (A), the content ratio of the acrylic acid alkyl ester unit in the acrylic acid ester unit is, for example, 50 to 100 mol%, preferably 70 to 100 mol% in terms of the monomer constituting the polymer block (A). is there. In addition, in a polymer block (A), the content rate of the acrylic acid alkylester unit in an acrylic ester unit is 50-100 mass%, for example, Preferably it is 70-100 mass%.

  In addition, the polymer block (A) may have 1 type, or 2 or more types of units derived from monomers other than the acrylate unit.

In the nitroxide polymer (A1), the nitroxide structure having an organic phosphorus unit usually has a nitroxy free radical (N—O.).
The nitroxide structure having an organophosphorus unit is, for example, a structure represented by the following formula (1).

(In the formula, R ¹ represents a hydrogen atom or a substituent, R ² represents a linking group, and X represents an organophosphorus unit.)

In R ¹ , examples of the substituent include a hydrocarbon group.
Examples of the hydrocarbon group include aliphatic groups [eg, C _1-10 alkyl groups (for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, etc. ), Preferably C _1-4 alkyl group etc.], alicyclic group [eg C _3-12 cycloalkyl group (eg cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group etc.), preferably C _3-7 cycloalkyl group etc.], aromatic group {eg C _6-20 aromatic group [eg C _6-20 aryl group (eg phenyl group, o-tolyl group, m-tolyl group, p-tolyl group] Group, 2,3-xylyl group, 1-naphthyl group and the like), C _7-20 aralkyl group (eg benzyl group and the like)} and the like. The hydrocarbon group may further have a substituent (for example, a halogen atom).

In Formula (1), R ¹ is preferably an aliphatic group, more preferably a C _1-10 alkyl group, and even more preferably a C _1-4 alkyl group.

In R ² , examples of the linking group include a hydrocarbon group.
Examples of the hydrocarbon group include aliphatic groups [eg, C _1-10 alkyl groups (for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, etc. ), Preferably a C _1-5 alkyl group], an alicyclic group [for example, a C _3-12 cycloalkyl group (eg, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, etc.), preferably a C _{3 -7} cycloalkyl group etc.], aromatic group {eg C _6-20 aromatic group [eg C _6-20 aryl group (eg phenyl group, o-tolyl group, m-tolyl group, p-tolyl group] , 2,3-xylyl group, 1-naphthyl group, etc.), C _7-20 aralkyl group (eg, benzyl group, etc.)]} and the like. The hydrocarbon group may further have a substituent (for example, a halogen atom).

In Formula (1), R ² is preferably an aliphatic group, more preferably a C _1-10 alkyl group, and even more preferably a C _1-5 alkyl group.

In X, the organic phosphorus unit may be a group containing phosphorus (phosphorus-containing group).
The phosphorus-containing group preferably includes at least a structure represented by a P (═O) OR ³ structure (R ³ represents a hydrogen atom or a hydrocarbon group).
In R ³ , the hydrocarbon group includes, for example, an aliphatic group [for example, a C _1-10 alkyl group (for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert group, -Butyl group etc., preferably C _1-4 alkyl group etc.], alicyclic group (eg C _3-12 cycloalkyl group etc.), aromatic group (eg C _6-20 aromatic group etc.) Etc.

R ³ is preferably an aliphatic group, more preferably a C _1-10 alkyl group, and even more preferably a C _1-4 alkyl group.

  As the organophosphorus unit, a structure represented by the following formula (2) is preferable.

[Wherein R ³ represents a hydrogen atom or a hydrocarbon group, and Y represents a hydrogen atom or —OR ⁴ (wherein R ⁴ represents a hydrogen atom or a hydrocarbon group). ]

In R ³ , examples of the hydrocarbon group include the hydrocarbon groups described above.

In R ⁴ , the hydrocarbon group includes, for example, an aliphatic group [for example, a C _1-10 alkyl group (for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert group, -Butyl group etc., preferably C _1-4 alkyl group etc.], alicyclic group (eg C _3-12 cycloalkyl group etc.), aromatic group (eg C _6-20 aromatic group etc.) Etc.

R ⁴ is preferably an aliphatic group, more preferably a C _1-10 alkyl group, and even more preferably a C _1-4 alkyl group.

In particular, in formula (2), ^{R 3} is a _{C 1-4} alkyl group, Y is preferably a hydrogen atom or -OR ^{4, R 3} is a _{C 1-4} alkyl group, Y is - More preferably, it is OR ⁴ and R ⁴ is a C _1-4 alkyl group.

Among the above, the nitroxide structure having an organic phosphorus unit is particularly preferably a structure represented by the above formula (1), wherein R ¹ is a C _1-4 alkyl group and R ² is a C _1-5 alkyl group. , X is a structure represented by the above formula (2), R ³ is a C _1-4 alkyl group, and Y is a hydrogen atom or —OR ⁴ .
Examples of the nitroxide structure having an organophosphorus unit include a structure represented by the following formula (1-1).

In the nitroxide polymer (A1), the polymer block (A) is usually a chain.
Further, the nitroxide polymer (A1) may have a plurality of nitroxide structures having an organic phosphorus unit.
In the nitroxide polymer (A1), the nitroxide structure having an organophosphorus unit may be at the ends of the polymer block (A), but is preferably at both ends of the polymer block (A).
In particular, the nitroxide polymer (A1) preferably has a nitroxide structure having an organophosphorus unit at both ends of the chain polymer block (A). By using such a nitroxide polymer (A1), a block copolymer having polymer blocks (B) on both sides of the polymer block (A) can be efficiently obtained.

  Although the weight average molecular weight (Mw) by the GPC measuring method of a nitroxide polymer (A1) is not specifically limited, For example, it is 40-300,000, Preferably it is 5-250,000.

  As the nitroxide polymer (A1), a commercially available product may be used. For example, Flexibloc (registered trademark) D2 (manufactured by Arkema France) may be used.

[Monomer (B1)]
The monomer (B1) contains at least a methacrylic acid ester and a 2-hydroxymethylacrylic acid monomer.
Although it does not specifically limit as methacrylic acid ester, For example, aliphatic methacrylate [For example, methacrylic acid alkylester (For example, _C1-18 alkyl methacrylate, such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, etc.) etc.], Alicyclic methacrylates [eg, methacrylic acid cycloalkyl esters (eg, C _3-20 cycloalkyl methacrylates such as cyclopropyl methacrylate, cyclobutyl methacrylate, etc.), cross-linked cyclic methacrylates (eg, isobornyl methacrylate], etc.], aromatic family methacrylate [for example, methacrylic acid aryl esters (e.g., phenyl methacrylate, methacrylic acid C _6-20 aryl such as methacrylic acid o- tolyl), methacrylic acid aralkyl ester (e.g., methacrylic bae Methacrylic acid _{C 6-10} aryl _{C 1-4} alkyl Jill etc.), methacrylic acid phenoxyalkyl (for example, methacrylic acid phenoxy _{C 1-4} alkyl), etc.] or the like, such as methacrylic acid phenoxyethyl is. These can use 1 type (s) or 2 or more types.

Among these methacrylic acid esters, from the viewpoint of improving transparency, it is preferable that at least an alkyl methacrylate ester is included, more preferably at least C _1-18 alkyl methacrylate is included, and at least methyl methacrylate is included. More preferably.

  The content ratio of the methacrylic acid alkyl ester in the methacrylic acid ester is, for example, 50 to 95% by mass, preferably 70 to 90% by mass. In addition, the content rate of the methacrylic acid alkylester in methacrylic acid ester is 50-95 mol%, for example, Preferably it is 70-90 mol%.

The 2-hydroxymethylacrylic acid-based monomer is not particularly limited. For example, aliphatic 2- (hydroxymethyl) acrylate {for example, 2- (hydroxymethyl) acrylic acid alkyl ester [for example, 2- (hydroxymethyl) acrylic 2- (hydroxymethyl) ethyl acrylate, 2- (hydroxymethyl) acrylic acid n-propyl, 2- (hydroxymethyl) acrylic acid isopropyl, 2- (hydroxymethyl) acrylic acid n-butyl, etc. C _1-18 alkyl (hydroxymethyl) acrylate, preferably C _1-12 alkyl 2- (hydroxymethyl) acrylate] etc.], 2- (hydroxymethyl) acrylic acid and the like. These can be used alone or in combination of two or more.

Among these 2-hydroxymethylacrylic acid monomers, 2- (hydroxymethyl) acrylic acid alkyl ester is preferable, 2- (hydroxymethyl) acrylic acid C _1-12 alkyl is more preferable, and 2- (hydroxymethyl) acrylic. More preferred is methyl acid.

  In the monomer (B1), the mass ratio of the methacrylic acid ester and the 2-hydroxymethylacrylic acid monomer is not particularly limited, but is, for example, 60/40 to 95/5, preferably 70/30 to 93/7, more preferably 75/25 to 90/10.

The monomer (B1) may contain a monomer other than the methacrylic acid ester and the 2-hydroxymethylacrylic acid monomer.
Other monomers include, for example, styrene monomers [eg, styrene, vinyl toluene, styrene having a substituent (eg, halogen group, alkoxy group, alkyl group, hydroxy group, etc.) (eg, α-methylstyrene, Chlorostyrene, etc.), styrenesulfonic acid or salts thereof, etc.], methacrylic acid, acrylic acid, vinyl compounds [eg, vinyl esters (eg, vinyl acetate), etc.], α, β-unsaturated nitriles (eg, acrylonitrile, methacrylo) Nitriles), olefins (eg, C _2-10 alkenes such as ethylene, propylene, 1-butene, isobutylene, 1-octene, etc.) and the like. These other monomers can be used alone or in combination of two or more.
The other monomer can be appropriately selected depending on the use of the block copolymer, but from the viewpoint of adjusting optical properties, it is preferable to include a styrene monomer, and more preferably to include styrene.

  In the monomer (B1), the content of the methacrylic acid ester and the 2-hydroxymethylacrylic acid monomer is, for example, 50 to 95% by mass, preferably 70 to 90% by mass. In the monomer (B1), the content ratio of the methacrylic acid ester and the 2-hydroxymethylacrylic acid monomer is, for example, 50 to 95 mol%, preferably 70 to 90 mol%.

  When the monomer (B1) contains another monomer, the content ratio of the other monomer is, for example, 1 to 20 with respect to 100 parts by mass of the total amount of the methacrylic acid ester and the 2-hydroxymethylacrylic acid monomer. Part by mass, preferably 1 to 10 parts by mass.

[Method for producing block copolymer]
In the polymerization step (I) of the nitroxide polymer (A1) and the monomer (B1), a block copolymer having a polymer block (A) and a polymer block containing a methacrylic acid ester unit and a 2-hydroxymethylacrylic acid monomer unit (1) is formed. Along with the formation of the block copolymer (1), a lactone ring structure is formed between the methacrylic acid ester unit and the 2-hydroxymethylacrylic acid monomer unit, and has a polymer block (A) and a polymer block (B). A block copolymer is obtained.

The block copolymer (1) may be at least partially cyclized or may not be cyclized. That is, the block copolymer (1) may have a lactone ring, may be the block copolymer of the present invention, or may not have a lactone ring.
In the production method of the present invention, it is preferable to form a lactone ring structure at least in the polymerization step (I) of the nitroxide polymer (A1) and the monomer (B1).

The lactone ring structure is formed by intramolecular and / or intermolecular cyclization reaction (dealcoholization reaction) between adjacent or adjacent methacrylic ester units and 2-hydroxymethylacrylic acid monomer units in the block copolymer (1). ) Can be done.
Although the reason why the cyclization reaction proceeds in the polymerization step (I) of the nitroxide polymer (A1) and the monomer (B1) is not clear, the organophosphorus unit of the nitroxide polymer (A1) is used as a catalyst for the cyclization reaction. It may be functioning.

The polymerization method of the nitroxide polymer (A1) and the monomer (B1) is usually living radical polymerization.
The block copolymer (1) can be formed by polymerizing the nitroxide polymer (A1) and the monomer (B1) via the nitroxide structure of the nitroxide polymer (A1).

The polymerization method of the nitroxide polymer (A1) and the monomer (B1) is preferably solution polymerization.
Although superposition | polymerization temperature is not specifically limited, For example, it is 80-130 degreeC, Preferably, it is 90-120 degreeC.
The polymerization time in the polymerization step (I) is not particularly limited and can be appropriately selected according to the polymerization temperature. For example, it is 0.5 to 6 hours, preferably 1 to 3 hours.
In addition, it is preferable that superposition | polymerization makes dissolved oxygen 50 ppm or less by introduce | transducing inert gas, such as nitrogen.

Examples of the polymerization solvent include alcohol solvents (eg, methanol, ethanol, etc.), aromatic hydrocarbon solvents (eg, toluene, ethylbenzene, xylene, etc.), ketone solvents (eg, acetone, methyl isobutyl ketone, methyl ethyl ketone, etc.). ) And ester solvents (for example, butyl acetate and the like). Among these solvents, methanol, toluene, xylene and the like are particularly preferable. These solvents may be used alone or in combination of two or more.
The amount of the polymerization solvent used is preferably 10 to 80% by weight in the monomer composition in the polymerization system.

A catalyst may be used in the polymerization.
Although it does not specifically limit as a catalyst, For example, at least 1 sort (s) chosen from an acid, a base and these salts, a metal complex, and a metal oxide can be used. Kinds of acids, bases and salts thereof, metal complexes, and metal oxides are not particularly limited. When the block copolymer finally obtained, or the resin composition or resin molded product containing the polymer is used for an application in which transparency is regarded as important, the catalyst is not reduced in transparency, It is preferable to use it in a range where no adverse effects such as coloring occur.

The acid is not limited, and examples thereof include inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and phosphorous acid, and organic acids such as p-toluenesulfonic acid, phenylsulfonic acid, organic carboxylic acid, and phosphoric acid ester.
The base is not limited, and examples thereof include metal hydroxides, amines, imines, alkali metal derivatives, alkoxides, and ammonium hydroxide salts.

The salt of an acid and a base is not limited, For example, they are metal organic acid salt (for example, metal carboxylate), metal inorganic acid salt (for example, metal carbonate etc.).
As long as the metal of the metal organic acid salt or metal inorganic acid salt does not impair the properties of the finally obtained block copolymer, resin composition or resin molded article, and does not cause environmental pollution at the time of disposal. For example, alkali metals such as lithium, sodium, and potassium; alkaline earth metals such as magnesium, calcium, strontium, and barium; zinc; zirconium and the like. Among these, zinc is preferable.

The carboxylic acid constituting the metal carboxylate is not limited, and for example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, octanoic acid, octylic acid, nonanoic acid, decanoic acid, lauric acid, Myristic acid, palmitic acid, stearic acid, behenic acid, tridecanoic acid, pentadecanoic acid, heptadecanoic acid, lactic acid, malic acid, citric acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, adipic acid.
As a specific metal carboxylate, zinc acetate, zinc propionate, zinc octylate, or zinc stearate is preferable.

A metal complex is not limited, For example, the example of the organic component is acetylacetone.
The metal oxide is not limited and is, for example, zinc oxide, calcium oxide, or magnesium oxide.

Among these exemplified catalysts, acid and base salts are preferable, metal organic acid salts are more preferable, and metal carboxylates are particularly preferable.
In addition, the usage-amount of a catalyst is not specifically limited.

In the polymerization step (I), polymerization may be performed in the presence of a chain transfer agent.
Examples of the chain transfer agent include thiol compounds [eg, aliphatic thiols (eg, butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, decanetrithiol, alkanethiol of dodecyl mercaptan, preferably C _1-20 alkanethiol), alicyclic thiol (eg, cycloalkanethiol such as cyclohexyl mercaptan, preferably C _4-10 cycloalkanethiol), aromatic thiol (eg, thiophenol), mercaptocarboxylic acid or ester thereof (For example, octyl thioglycolate, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, octanoic acid - mercapto alkanoic acids or esters thereof such as mercaptoethyl ester, preferably a mercapto C _2-10 alkanoic acid or its alkyl ester), 1,8-organic thiol compounds such dimercapto-3,6, halides (For example, halogenated hydrocarbons such as carbon tetrachloride, carbon tetrabromide, methylene chloride, bromoform, bromotrichloroethane), unsaturated hydrocarbon compounds (for example, α-methylstyrene dimer, α-terpinene, γ-terpinene, dipentene) , Terpinolene, etc.). These may be used alone or in combination of two or more. Among these, it is preferable to use a thiol compound (for example, an organic thiol compound such as alkanethiol). By using a chain transfer agent, it is easy to improve the thermal stability of the resulting block copolymer.

  The amount of chain transfer agent used can be appropriately selected according to the type of chain transfer agent and the like, and is not particularly limited. For example, for 100 parts by mass of the total amount of nitroxide polymer (A1) and monomer (B1), for example, 0 0.001 to 10 parts by mass, preferably 0.01 to 5 parts by mass, more preferably about 0.05 to 3 parts by mass, and usually 0.01 to 1 part by mass (for example, 0.03 to 0) About 5 parts by mass).

In the polymerization step of the nitroxide polymer (A1) and the monomer (B1), the conversion rate (reaction rate) of the methacrylic acid ester is, for example, 10 to 60%, preferably 15 to 50%. Moreover, the conversion rate (reaction rate) of the 2-hydroxymethylacrylic acid monomer is, for example, 10 to 60%, preferably 15 to 50%.
The conversion rate of these monomers can be calculated from, for example, the amount of methacrylic acid ester and residual 2-hydroxymethylacrylic acid monomer remaining in the polymerization solution after completion of the polymerization reaction.
The formation of the lactone ring structure can be confirmed by detecting alcohol contained in the polymerization solution after the completion of the polymerization reaction.
The calculation of the monomer conversion rate and the detection of alcohol in the polymerization solution can be carried out using, for example, gas chromatography.

  In the polymerization step (I) of the nitroxide polymer (A1) and the monomer (B1), the mass ratio of the nitroxide polymer (A1) and the monomer (B1) is not particularly limited, but is, for example, 3/97 to 40/60, preferably 5 / 95 to 30/70, more preferably 7/93 to 25/75.

  Further, additional polymerization may be performed after the polymerization step (I) of the nitroxide polymer (A1) and the monomer (B1). By performing additional polymerization, it is possible to obtain a resin composition containing the block copolymer (1) without requiring removal of the remaining monomer, or to further advance the cyclization reaction. The additional polymerization is preferably performed by adding a radical polymerization initiator.

  Examples of the radical polymerization initiator include organic peroxides [for example, tert-amylperoxyisononanoate, t-amylperoxy-2-ethylhexanoate, tert-butylperoxy-3,5,5- Trimethylhexanate, tert-butyl peroxylaurate, tert-butyl peroxyisopropyl monocarbonate, tert-hexyl peroxyisopropyl monocarbonate, tert-butyl peroxyacetate, 1,1-bis (tert-butylperoxy) 3 , 3,5-trimethylcyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, tert-butylperoxy 2-ethylhexanate, tert-butylperoxyisobutyrate, tert-hexylperoxy-2- Tilhexanate, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane, etc.], azo compounds [eg, 2- (carbamoylazo) -isobutyronitrile 1,1′-azobis (1-cyclohexanecarbonitrile), 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), dimethyl 2,2′-azobis Isobutyrate, 2,2′-azobis (2,4,4-trimethylpentane), 2,2′-azobis (2-methylpropane) and the like]. A polymerization initiator may be used independently or may use 2 or more types together. In addition, the usage-amount of a polymerization initiator is not specifically limited.

In carrying out the additional polymerization, a chain transfer agent may be added. In the additional polymerization, even when a chain transfer agent is used, the same effects as when the chain transfer agent is used in the polymerization step (I) (for example, the effect of improving the thermal stability of the block copolymer) may be obtained. is there.
Examples of the chain transfer agent include the chain transfer agents exemplified above, for example, butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 2-mercaptopropionate. Organic thiol compounds such as octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, 2-mercaptoethyl ester octanoate, 1,8-dimercapto-3,6-dioxaoctane, decanetrithiol, dodecyl mercaptan; Halides such as carbon tetrachloride, carbon tetrabromide, methylene chloride, bromoform, bromotrichloroethane; α-methylstyrene dimer, α-terpinene, γ-terpinene, dipen Emissions, unsaturated hydrocarbon compounds such as terpinolene. These may be used alone or in combination of two or more. Among them, it is preferable to use an organic thiol compound having a hydrocarbon group having 3 or more carbon atoms. In addition, the usage-amount of a chain transfer agent is not specifically limited.

  The amount of chain transfer agent used can be appropriately selected according to the type of chain transfer agent and the like, and is not particularly limited. For example, for 100 parts by mass of the total amount of nitroxide polymer (A1) and monomer (B1), for example, 0 0.001 to 10 parts by mass, preferably 0.01 to 5 parts by mass, more preferably about 0.05 to 3 parts by mass, and usually 0.01 to 1 part by mass (for example, 0.03 to 0) About 5 parts by mass).

Moreover, when performing additional polymerization, you may add a monomer (B1) further. The monomer (B1) to be added may be one type or two or more types.
The monomer (B1) to be added is preferably another monomer in the monomer (B1) described above, and more preferably includes a styrene monomer, and further preferably includes styrene.

  Although the addition ratio of the monomer (B1) to add is not specifically limited, For example, 1-50 mass with respect to 100 mass parts of total amounts of the methacrylic acid ester and 2-hydroxymethylacrylic acid type monomer which were used by the polymerization process (I). Parts, preferably 2 to 30 parts by weight.

  The block copolymer obtained through the polymerization step (I) (additional polymerization step (II) as necessary) may be further subjected to a cyclization reaction. The cyclization reaction can be carried out by heating or devolatilizing the block copolymer. For example, a method of passing the block copolymer through a heated extruder having a vent, a method of heating and devolatilizing the block copolymer in an inert gas (for example, nitrogen gas) atmosphere or vacuum, etc. it can. In particular, when the additional polymerization step (II) is performed, cyclization (post-cyclization) may be performed together with or in the additional polymerization step (II) from the viewpoint of production efficiency and the like.

  The polymerization solution after completion of the polymerization reaction may be subjected to filtration, drying, addition of a solvent (for example, an aromatic hydrocarbon solvent such as toluene), heating, devolatilization, etc., as necessary. These methods are not particularly limited, and may be a conventionally known method.

In addition, in the polymerization step (I) and the additional polymerization step (II), other additives (for example, an ultraviolet absorber, an antioxidant, a stabilizer, a reinforcing material, a flame retardant, an antistatic agent, an organic filler, an inorganic filler, An anti-blocking agent, a resin modifier, an organic filler, an inorganic filler, a plasticizer, a lubricant, a retardation reducing agent, etc.) may be added to the polymerization system. Other additives may be added to the polymerization solution after completion of the polymerization reaction. The amount of other additives is not particularly limited.
Moreover, you may mix other resin (For example, a thermoplastic polymer etc.) etc. with the polymerization liquid after completion | finish of polymerization reaction. The compounding quantity of other resin is not specifically limited.

Examples of the ultraviolet absorber include benzophenone compounds, salicylate compounds, benzoate compounds, triazole compounds, triazine compounds, and the like.
Examples of the benzophenone compounds include 2,4-dihydroxybenzophenone, 4-n-octyloxy-2-hydroxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2-hydroxy-4-n- Examples include octyloxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 1,4-bis (4-benzoyl-3-hydroxyphenone) -butane and the like.

Examples of the silicate compound include pt-butylphenyl silicate.
Examples of the benzoate compound include 2,4-di-t-butylphenyl-3 ′, 5′-di-t-butyl-4′-hydroxybenzoate.

  Examples of the triazole compound include 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol, 2- (2H-benzotriazole-2- Yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2-benzotriazol-2-yl-4,6-di-tert-butylphenol, 2- [5-chloro (2H) -benzo Triazol-2-yl] -4-methyl-6-tert-butylphenol, 2- (2H-benzotriazol-2-yl) -4,6-di-tert-butylpheno 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol, 2- (2H-benzotriazol-2-yl) -4-methyl-6 (3,4,5,6-tetrahydrophthalimidylmethyl) phenol, methyl 3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate / polyethylene glycol 300 2- (2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2 -[2-Hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 3- (2H-benzotriazole 2-yl) -5- (1,1-dimethylethyl) -4-hydroxy -C7-9 side chain and straight chain alkyl esters.

  Furthermore, as triazine compounds, for example, 2-mono (hydroxyphenyl) -1,3,5-triazine compounds, 2,4-bis (hydroxyphenyl) -1,3,5-triazine compounds, 2,4, Examples include 6-tris (hydroxyphenyl) -1,3,5-triazine compounds, specifically 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5- Triazine, 2,4-diphenyl-6- (2-hydroxy-4-ethoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-propoxyphenyl) -1,3 5-triazine, 2,4-diphenyl- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-) Toxiphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2 -Hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4- Diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyethoxy) -1,3,5-triazine 2,4-bis (2-hydroxy-4-butoxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3-5-triazine, 2,4,6-tris (2-hydroxy 4-methoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-ethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2- Hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris ( 2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, 2,4,6 -Tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2 , 4,6 -Tris (2-hydroxy-4-benzyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-ethoxyethoxyphenyl) -1,3,5-triazine, 2 , 4,6-tris (2-hydroxy-4-butoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-propoxyethoxyphenyl) -1,3,5 Triazine, 2,4,6-tris (2-hydroxy-4-methoxycarbonylpropyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-ethoxycarbonylethyloxy) Phenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4- (1- (2-ethoxyhexyloxy) -1-oxopropa -2-yloxy) phenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-methoxyphenyl) -1,3,5-triazine, 2,4 6-tris (2-hydroxy-3-methyl-4-ethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-propoxyphenyl) -1, 3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3- Methyl-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1,3,5-triazine, 2,4 , 6-Tris (2-G Loxy-3-methyl-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-dodecyloxyphenyl) -1,3,5- Triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-benzyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4) -Ethoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-butoxyethoxyphenyl) -1,3,5-triazine, 2,4,6 -Tris (2-hydroxy-3-methyl-4-propoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-methoxycarbonylpro) Pyroxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-ethoxycarbonylethyloxyphenyl) -1,3,5-triazine, 2,4 And 6-tris (2-hydroxy-3-methyl-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1,3,5-triazine.

  Among them, 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4 is preferred because it is highly compatible with amorphous thermoplastic resins, particularly acrylic resins, and has excellent absorption characteristics. UV absorbers having-(3-alkyloxy-2-hydroxypropyloxy) -5-α-cumylphenyl] -s-triazine skeleton (alkyloxy; long-chain alkyloxy groups such as octyloxy, nonyloxy, decyloxy, etc.) It is done.

  Further, an ultraviolet absorber having a 2,4,6-tris (hydroxyphenyl) -1,3,5-triazine skeleton is preferably used, and 2,4,6-tris (2-hydroxy-4-long chain alkyloxy) is used. Group-substituted phenyl) -1,3,5-triazine skeleton and 2,4,6-tris (2-hydroxy-3-alkyl-4-long-chain alkyloxy group-substituted phenyl) -1,3,5-triazine skeleton The ultraviolet absorber having is a particularly preferred triazine-based ultraviolet absorber.

Examples of commercially available products include, for example, “Tinuvin 1577”, “Tinuvin 460”, “Tinuvin 477” (manufactured by BASF Japan), “Adeka Stab LA-F70” (manufactured by ADEKA), and triazole-based UV absorber. “ADK STAB LA-31” (manufactured by ADEKA) and the like can be mentioned.
These can be used alone or in combination of two or more.

Although antioxidant is not specifically limited, For example, well-known antioxidants, such as a phenol type, a phosphorus type, or a sulfur type, can be used by 1 type or in combination of 2 or more types.
Examples of phenolic antioxidants include n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, n-octadecyl-3- (3,5-di-t-butyl). -4-hydroxyphenyl) acetate, n-octadecyl-3,5-di-t-butyl-4-hydroxybenzoate, n-hexyl-3,5-di-t-butyl-4-hydroxyphenylbenzoate, n-dodecyl 3,5-di-t-butyl-4-hydroxyphenylbenzoate, neododecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, dodecyl-β- (3,5-di- t-butyl-4-hydroxyphenyl) propionate, ethyl-α- (4-hydroxy-3,5-di-t-butylphenyl) isobutyrate Octadecyl-α- (4-hydroxy-3,5-di-t-butylphenyl) isobutyrate, octadecyl-α- (4-hydroxy-3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2- (n-octylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, 2- (n-octylthio) ethyl-3,5-di-t-butyl-4-hydroxyphenyl acetate, 2 -(N-octadecylthio) ethyl-3,5-di-t-butyl-4-hydroxyphenyl acetate, 2- (n-octadecylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, 2- (2-hydroxyethylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, diethyl glycol bis- (3,5 -Di-t-butyl-4-hydroxy-phenyl) propionate, 2- (n-octadecylthio) ethyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, stearamide-N, N -Bis- [ethylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], n-butylimino-N, N-bis- [ethylene-3- (3,5-di-t -Butyl-4-hydroxyphenyl) propionate], 2- (2-stearoyloxyethylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, 2- (2-stearoyloxyethylthio) ethyl- 7- (3-Methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,2-propylene glycol bis- [3- (3,5 Di-t-butyl-4-hydroxyphenyl) propionate], ethylene glycol bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], neopentyl glycol bis- [3- (3 , 5-di-t-butyl-4-hydroxyphenyl) propionate], ethylene glycol bis- (3,5-di-t-butyl-4-hydroxyphenyl acetate), glycerin-1-n-octadecanoate- 2,3-bis- (3,5-di-t-butyl-4-hydroxyphenyl acetate), pentaerythritol tetrakis- [3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) Propionate], 1,1,1-trimethylolethanetris- [3- (3,5-di-tert-butyl-4-hydroxypheny ) Propionate], sorbitol hexa- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2-hydroxyethyl-7- (3-methyl-5-tert-butyl-4-hydroxy Phenyl) propionate, 2-stearoyloxyethyl-7- (3-methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,6-n-hexanediol bis [(3 ', 5'-di-t -Butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis (3,5-di-t-butyl-4-hydroxyhydrocinnamate), 1,3,5-trimethyl-2,4,6-tris (3 , 5-Di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [1,1-dimethyl-2- [β- (3-t- Til-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5,5] -undecane, 2,4-di-t-amyl-6- [1 -(3,5-di-t-amyl-2-hydroxyphenyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate and the like.

  Examples of the thioether-based antioxidant include pentaerythrityl tetrakis (3-laurylthiopropionate), dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, distearyl. -3,3'-thiodipropionate and the like.

  Examples of the phosphoric acid antioxidant include tris (2,4-di-t-butylphenyl) phosphite, 2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [ d, f] [1,3,2] dioxaphosphin-6-yl] oxy] -N, N-bis [2-[[2,4,8,10-tetrakis (1,1 dimethylethyl)] Dibenzo [d, f] [1,3,2] dioxaphosphin-6-yl] oxy] -ethyl] ethanamine, genyltridecyl phosphite, triphenyl phosphite, 2,2-methylenebis (4,6 -Di-t-butylphenyl) octyl phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite DOO, cyclic neopentanetetraylbis (2,6-di -t- butyl-4-methylphenyl) phosphite, and the like.

  Examples of the thermoplastic polymer include poly (meth) acrylate, poly (meth) acrylate copolymer and modified products thereof, and acrylic resins such as poly (meth) acrylate having a ring structure; polyethylene, polypropylene, ethylene-propylene Copolymer, olefin polymer such as poly (4-methyl-1-pentene); vinyl halide polymer such as polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride; polystyrene, styrene-methyl methacrylate copolymer, Styrenic polymers such as styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene block copolymer; polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate; cellulose triacetate, cellulose acetate Cellulose acylates such as carbonate propionate and cellulose acetate butyrate; polyamides such as nylon 6, nylon 66 and nylon 610; polyacetals; polycarbonates; polyphenylene oxides; polyphenylene sulfides; polyether ether ketones; polysulfones; Benzylene; Polyamideimide; Rubber polymer such as ABS resin and ASA resin blended with polybutadiene rubber or acrylic rubber.

[Block copolymer]
Using the above-described production method, a block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylic acid ester Can be obtained.

  In the present invention, a novel block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylic acid ester is provided. Can be provided. Such a block copolymer is not particularly limited in its production method, but it may usually be produced by the production method.

  Such a block copolymer may be a polyblock copolymer (for example, a di-deca block copolymer). The block copolymer preferably has a polymer block (B) at least on both sides of the polymer block (A) (has (B)-(A)-(B)). Moreover, it is preferable that a block copolymer has the said nitroxide structure which has the said organic phosphorus unit. The block copolymer preferably has the nitroxide structure at the ends, and more preferably at both ends.

  As the lactone ring structure possessed by the block copolymer, a unit represented by the following formula (3) is preferred.

(In the formula, R ⁵ , R ⁶ and R ⁷ are the same or different and represent a hydrogen atom or a substituent.)

In the formula (3), examples of the substituent include organic residues such as a hydrocarbon group.
Examples of the hydrocarbon group include an aliphatic group (for example, a C _1-20 alkyl group such as a methyl group, an ethyl group, and a propyl group) and an aromatic group (for example, a C _6-20 aromatic group such as a phenyl group and a naphthyl group). Group hydrocarbon group, etc.). The hydrocarbon group may be further substituted with a substituent (for example, at least one group selected from a halogen atom, a hydroxyl group, a carboxyl group, an ether group, and an ester group). The hydrocarbon group may have these substituents alone or in combination of two or more.

In Formula (3), R ⁵ is preferably a hydrogen atom, R ⁶ is preferably a C _1-20 alkyl group, and R ⁷ is preferably a methyl group.

In the polymer block (B) of the block copolymer, the content of the lactone ring structure is, for example, 5 to 40% by weight, preferably 7 to 30% by weight, from the viewpoint that the block copolymer has excellent heat resistance. More preferably, it is 10 to 25% by weight. In addition, in the polymer block (B) of the block copolymer, the content ratio of the lactone ring structure is, in terms of the monomer constituting the polymer block (B), from the viewpoint that the block copolymer has excellent heat resistance, etc. For example, it is 4-35 mol%, preferably 6-25 mol%, more preferably 8-20 mol%.
In addition, when a block copolymer is a triblock copolymer, the content rate of the lactone ring structure in each polymer block (B) should just be such a range.

  When the polymer block (B) of the block copolymer has other units, the content of other units in the polymer block (B) is, for example, 30% by weight or less (for example, 0.1 to 20% by weight), preferably Is 15% by weight or less (for example, 1 to 10% by weight). In addition, the content rate of the other unit in a polymer block (B) is 30 mol% or less (for example, 0.1-20 mol%), for example, Preferably it is 15 mol% in conversion of the monomer which comprises a polymer block (B). The following (for example, 1 to 10 mol%).

In particular, when the block copolymer is used for optical applications such as an optical film, it is preferable to have a styrenic unit from the viewpoint of being able to offset the positive birefringence of the lactone ring.
Although the content rate of the styrene-type unit in a polymer block (B) can be suitably selected according to a desired optical characteristic etc., for example, 0.1-15 weight%, Preferably it is 1-10 weight%, More preferably, it is 3-8. % By weight. In addition, the content rate of the styrene-type unit in a polymer block (B) is 0.1-20 mol% in conversion of the monomer which comprises a polymer block (B), Preferably it is 1-12 mol%, More preferably, it is 3- 10 mol%.
In addition, when a block copolymer is a triblock copolymer, the content rate of the other unit (for example, styrene-type unit etc.) in each polymer block (B) should just be the above ranges.

Although the weight average molecular weight (Mw) by the GPC measuring method of a block copolymer is not specifically limited, For example, 0.5 to 500,000, Preferably it is 5 to 300,000, More preferably, it is 80 to 200,000.
The weight average molecular weight (Mw) of the block copolymer is 150,000 or more (for example, 160,000 to 1,000,000), preferably 170,000 or more (for example, 175,000 to 800,000), more preferably 200,000. It may be above (for example, 230,000 to 600,000), particularly 250,000 or more (for example, 270,000 to 500,000), 300,000 or more (for example, 300 to 1,000,000, preferably 300 to 500,000). May be. By setting the molecular weight in such a relatively large range, it is easy to obtain a block copolymer excellent in thermal stability and the like, which is preferable.
The molecular weight Mw may be a value measured by GPC in terms of polystyrene, for example.

  The molecular weight distribution of the block copolymer is not particularly limited, but can be selected from a range of about 3 or less, for example 1.1 to 2.7, preferably 1.2 to 2.3, more preferably 1.3 to 1. .9. In particular, the molecular weight distribution of the block copolymer is 2.5 or less (for example, 1 to 2.3), preferably 2 or less (for example, 1.1 to 1.9), more preferably 1.8 or less (for example, 1.2-1.7).

In the block copolymer, the ratio of the weight average molecular weight (Mw) of the polymer block (A) to the polymer block (B) is not particularly limited, and is, for example, 1: 0.5 to 1: 3, preferably 1: 1 to 1: 2.
When the block copolymer is a triblock copolymer, the ratio of the weight average molecular weight (Mw) between the polymer block (A) and each polymer block (B) may be in such a range.

  The thermal decomposition temperature of the block copolymer is, for example, 300 ° C. or higher (eg, 300 ° C. to 350 ° C.), preferably 310 ° C. to 350 ° C., although it depends on the type of monomer used and the content of the lactone ring structure. is there.

  The glass transition temperature (Tg) of the block copolymer is, for example, 110 ° C. or higher (for example, 110 ° C. to 200 ° C.), preferably 115 ° C. to 120 ° C., although it depends on the type of monomer used and the content of the lactone ring structure. It is 160 degreeC, More preferably, it is 120 to 150 degreeC.

The present invention also includes a resin composition containing the block copolymer. Such a resin composition should just contain the said block copolymer, and may contain other resin. Other resins can be appropriately selected depending on the application and are not particularly limited. For example, when additional polymerization is performed as described above, a resin composition containing the block copolymer [for example, a mixture of a block copolymer and a polymer containing the monomer (B1) as a polymerization component (polymer) Blend)] is obtained.
Moreover, the resin composition may contain a conventional additive according to a use etc.

  In addition, you may select the physical property (Mw, molecular weight distribution, thermal decomposition temperature, Tg, etc.) of the resin composition containing such a block copolymer from the range similar to the physical property about the said block copolymer.

[the film]
The molded product (for example, a film or sheet) of the block copolymer or resin composition (for example, the block copolymer or resin composition obtained by the production method of the present invention) of the present invention contains a block copolymer. Although it is not particularly limited as long as it is a molded product, it is preferably used for optical purposes, and examples thereof include an optical protective film, an optical film, and an optical sheet. The optical protective film is not particularly limited as long as it is a film that protects an optical component. Examples include child protective films.
The optical film is not particularly limited as long as it has excellent optical characteristics, but preferably a retardation film, a zero retardation film (in-plane, thickness direction retardation is extremely small), a viewing angle compensation film, a light diffusion film. Examples thereof include a film, a reflection film, an antireflection film, an antiglare film, a brightness enhancement film, and a conductive film for a touch panel.
Examples of the optical sheet include a diffusion plate, a light guide, a retardation plate, a zero retardation plate, and a prism sheet.
In addition, a shaping | molding method is not specifically limited, You may follow a conventionally well-known method.

  For example, a film can be obtained by forming a block copolymer by a known film formation method [for example, solution casting method (solution casting method), melt extrusion method, calendar method, compression molding method, etc.]. it can. As the film forming method, a solution casting method, a melt extrusion method, or the like is preferable.

  During film formation, if desired, a solvent, other resins (for example, thermoplastic polymers), other additives (for example, ultraviolet absorbers, antioxidants, stabilizers, reinforcing materials, flame retardants) , Antistatic agents, organic fillers, inorganic fillers, anti-blocking agents, resin modifiers, organic fillers, inorganic fillers, plasticizers, lubricants, retardation reducing agents, etc.) can be mixed with block copolymers. Good.

  Although the compounding quantity of the ultraviolet absorber in a film is not specifically limited, It is preferable that it is 0.01-10 mass% in a film, More preferably, it is 0.05-5 mass%. If the blending amount is too small, the contribution to improving the weather resistance is low, and if it is too large, the mechanical strength may be lowered or yellowing may be caused.

  An apparatus for performing the solution casting method is, for example, a drum type casting machine, a band type casting machine, or a spin coater.

  The solvent used for the solution casting method is not limited as long as the block copolymer is dissolved. Examples of the solvent include aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as cyclohexane and decalin; esters such as ethyl acetate and butyl acetate; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. Alcohols such as methanol, ethanol, isopropanol, butanol, isobutanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve; ethers such as tetrahydrofuran and dioxane; halogenated hydrocarbons such as dichloromethane, chloroform and carbon tetrachloride; dimethylformamide; dimethyl sulfoxide is there. These solvents can be used alone or in combination of two or more.

  Examples of the melt extrusion method include a T-die method and an inflation method. The molding temperature during melt extrusion is preferably 150 to 350 ° C, more preferably 200 to 300 ° C.

  When the T-die method is selected, for example, a belt-like film can be formed by attaching a T-die to the tip of a known extruder. The formed belt-like film may be wound up on a roll to form a film roll. In the melt extrusion method, from the formation of an acrylic resin by mixing materials to the formation of a film using the resin can be performed continuously. A band-shaped optical film may be obtained by forming an easy-adhesion layer on the band-shaped film.

  The film may be a biaxially stretched film from the viewpoint of increasing mechanical strength. The biaxially stretched film may be a simultaneous biaxially stretched film or a sequential biaxially stretched film. The direction of the slow axis of the stretched film may be the film flow direction, the width direction, or an arbitrary direction.

Although the thickness of a film is not specifically limited, Although it can adjust suitably by a use etc., it is 1-400 micrometers, Preferably it is 5-200 micrometers, More preferably, it is 10-100 micrometers, More preferably, it is 20-60 micrometers.
For example, when used for applications such as protective films, antireflection films, polarizing films, etc. used in image display devices such as liquid crystal display devices and organic EL display devices, preferably 1 to 250 μm, more preferably 10 to 100 μm, Preferably it is 20-80 micrometers.
Moreover, when using for uses, such as a transparent conductive film used for an ITO vapor deposition film, a silver nanowire film, a metal mesh film etc., for example, Preferably it is 20-400 micrometers, More preferably, it is 30-350 micrometers, More preferably, it is 40. ˜300 μm.

  The haze of the film is preferably 1% or less (for example, 0 to 1%), more preferably 0.5% or less (for example, 0 to 0.5%). The haze is measured based on the specification of JIS K7136.

  The b value of the film is preferably 2% or less (for example, 0.1 to 2%), more preferably 1.5% or less (for example, 0.1 to 1.5%), and still more preferably 1% or less ( For example, 0.1 to 1%), and most preferably 0.5% or less (for example, 0.1 to 0.5%).

  Tg of a film is 110 degreeC or more (for example, 110 degreeC-200 degreeC), for example, Preferably it is 115 degreeC-160 degreeC.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. It is also possible to implement, and they are all included in the technical scope of the present invention.
In the following description, “%” represents “mass%” and “part” represents “part by mass” unless otherwise specified.

<Weight average molecular weight>
The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (D) of the block polymer, polymer and composition were determined by gel permeation chromatography (GPC) in terms of polystyrene. The apparatus and measurement conditions used for the measurement are as follows.
System: Tosoh GPC system HLC-8220
Measurement side column configuration Guard column: Tosoh, TSK guard column Super HZ-L
-Separation column: Tosoh, TSKgel SuperHZM-M 2 in series connection Reference side column configuration-Reference column: Tosoh, TSKgel SuperH-RC
Developing solvent: Chloroform (Wako Pure Chemical Industries, special grade)
Flow rate of developing solvent: 0.6 mL / min Standard sample: TSK standard polystyrene (manufactured by Tosoh, PS-oligomer kit)
Column temperature: 40 ° C

<Block Polymer, Polymer Monomer Conversion and Determination of Alcohol>
Monomer conversion and quantification of produced alcohol were determined by measurement using gas chromatography (manufactured by Shimadzu Corporation, apparatus name: GC-2014).

<Glass transition temperature>
The glass transition temperature (Tg) was determined in accordance with JIS K7121 regulations. Specifically, a differential scanning calorimeter (manufactured by Rigaku, DSC-8230) is used, and a sample of about 10 mg is heated from normal temperature to 200 ° C. (temperature increase rate: 20 ° C./min) in a nitrogen gas atmosphere. The DSC curve was evaluated by the starting point method. Α-alumina was used as a reference.

<Thermal decomposition temperature>
The thermal decomposition temperature was analyzed by the following method (dynamic TG method).
Measuring apparatus: differential type differential thermal balance (ThermoPlus 2TG-8120 dynamic TG, manufactured by Rigaku Corporation)
Measurement conditions: Sample amount 10 mg
Temperature increase rate: 10 ° C / min
Atmosphere: Nitrogen flow 200 mL / min
Method: Step-like isothermal control method (controlled to a mass reduction rate value of 0.005% / s or less in the range from 150 ° C to 500 ° C)

<Foaming properties>
The foamability of the block polymer and polymer was evaluated by measuring the amount of foaming during heating. That is, a block polymer dried in an oven at 80 ° C. for at least 12 hours is loaded into a melt indexer cylinder defined in JIS-K7210, held at 290 ° C. for 20 minutes, and then extruded into a strand. The number of bubbles generated between the upper standard line and the lower standard line of the obtained strand was counted and expressed as the number per 1 g of the thermoplastic resin composition.
○: 0 to 10 pieces, Δ: 10 to 20 pieces, ×: 20 pieces or more

<Heat degradation test (filter test)>
Under nitrogen, 0.5 g of a sample was sealed in a test tube, heated at 240 ° C. for 1 hour using a heat block, chloroform was dissolved in 49.5 g, and a 1 wt% solution was prepared. 2 ml of this solution was taken in a syringe and filtered with a chromatodisc (GL Science Co., 0.2 μm, 4N) set at the tip of the syringe. A filter that was filtered 2 ml or more was marked as ◎, a filter clogged when it was 1 ml or more but less than 2 ml, and a case that the filter was clogged when it was less than 1 ml.

<Thickness of film>
The thickness of the film was measured using a Digimatic Micrometer (Mitutoyo). Samples for measuring and evaluating the physical properties of the film, including the physical properties indicating the evaluation methods below, were obtained from the central portion in the width direction of the film.

<Haze of film>
The haze of the film was measured by immersing 1,2,3,4-tetrahydronaphthalene (tetralin) in a quartz cell using NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd. Calculated as internal haze value.

<Folding resistance>
The number of folding times of the film was measured according to JIS P8115. Specifically, two types of test films having a length of 90 mm and a width of 15 mm, whose longitudinal directions are the MD direction and the TD direction, were used after being allowed to stand at 23 ° C. and 50% RH for 1 hour or longer. Using a folding fatigue tester (Toyo Seiki, DA type), the test was conducted under the conditions of a bending angle of 135 °, a bending speed of 175 cpm, and a load of 200 g. I asked for each. The number of folds so that the fold line is perpendicular to the film flow direction during film _formation is represented as MIT _MD, and the number of folds so that the fold line is parallel to the flow direction is represented as MIT _TD .

<Internal Haze change rate after heating>
Using the unstretched film having a thickness of 160 μm obtained in Examples 6 to 11 and Comparative Examples 3 to 4, it was pressed at 250 ° C. for 2 minutes with a manual heating press (Imoto Seisakusho, IMC-180C type) to 50 μm. The internal haze of the film was determined. The internal Haze was measured by filling a quartz cell with 1,2,3,4-tetrahydronaphthalene (tetralin) using NDH-1001DP manufactured by Nippon Denshoku Industries Co., Ltd., and immersing the film in it.
Next, the internal haze after heating at 250 ° C. for 20 minutes was determined with a manual heating press, and the internal haze change rate (%) before and after heating was determined from these internal haze values.

Example 1: Synthesis and cyclization of block polymer by nitroxide polymerization A reactor equipped with a stirrer, a temperature sensor, a condenser tube, and a nitrogen introduction tube was charged with polybutyl acrylate having a nitroxide structure having phosphonate ester units at both ends. 58 parts of 60% toluene solution (Flexibloc® D2, Arkema France), 21 parts methyl 2-hydroxymethyl acrylate (RHMA), 84 parts methyl methacrylate (MMA), and 40 parts as polymerization solvent Of toluene was charged, and the temperature was raised to 105 ° C. while passing nitrogen through the toluene. Thereafter, solution polymerization was allowed to proceed for 3 hours under reflux at about 105 to 110 ° C. The reaction rate calculated from the amount of monomers in the polymerization solution at this time was 30% for MMA and 28% for RHMA. Furthermore, 0.1% of methanol was detected from the obtained polymerization solution. This supports the occurrence of intramolecular lactone cyclization accompanying transesterification with the polymerization reaction. In addition, in the obtained polymer, the theoretical concentration of methanol (molecular weight 32) in the polymerization solution generated when 100% of RHMA (molecular weight 116) units undergo cyclization reaction is 21 × 0.28 × (32/116). Since /(58+21+84+40)×100=0.8%, the cyclization reaction rate can be calculated as 0.1 / 0.8 = 13%.
Next, the residual monomer and solvent were removed at 2.6 kPa and 80 ° C. for about 2 hours, and then 150 parts of toluene was added and dissolved uniformly, then charged in a pressure vessel made of SUS316 and replaced with a nitrogen atmosphere at 240 ° C., 2 And held at 5 MPa for 90 minutes. Thereafter, the solvent is removed from the solution at 240 ° C. under vacuum to obtain a triblock copolymer (A-1) consisting of a lactone cyclized product of a copolymer consisting of butyl polyacrylate in the central block and MMA and RHMA on both sides. Got.
A-1 had a weight average molecular weight of 216,000, a number average molecular weight of 83,000, a molecular weight distribution of 2.6, a glass transition temperature of 125 ° C., and a thermal decomposition temperature of 327 ° C. Moreover, it was (circle) when the foamability evaluation of A-1 was implemented.

Example 2: Block polymer synthesis and cyclization by nitroxide polymerization 10 parts Flexibloc® D2, 10.8 parts 2-hydroxy in a reactor equipped with a stirrer, temperature sensor, condenser, nitrogen inlet Methyl methyl acrylate (RHMA), 75.2 parts of methyl methacrylate (MMA), 2.3 parts of styrene (ST) and 96.2 parts of toluene as a polymerization solvent were charged, and nitrogen was passed through the solution at 105 ° C. The temperature was raised to. Thereafter, solution polymerization was allowed to proceed for 3 hours under reflux at about 105 to 110 ° C. The reaction rate calculated from the amount of monomers in the polymerization solution at this time was 23% for MMA, 25% for RHMA, and 44% for ST. Furthermore, 0.1% of methanol was detected from the obtained polymerization solution. This supports the occurrence of intramolecular lactone cyclization accompanying transesterification with the polymerization reaction. In the obtained polymer, the theoretical concentration of methanol in the polymerization solution produced when 100% of the RHMA units undergo a cyclization reaction is 10.8 × 0.25 × (32/116) / (10 + 10.8 + 75. Since 2 + 2.3 + 96.2) × 100 = 0.38%, the cyclization reaction rate can be calculated as 0.1 / 0.38 = 26%.
Next, the residual monomer and solvent were removed at 2.6 kPa and 80 ° C. for about 2 hours, and then 150 parts of toluene was added and dissolved uniformly, then charged in a pressure vessel made of SUS316 and replaced with a nitrogen atmosphere at 240 ° C., 2 And held at 5 MPa for 90 minutes. Thereafter, the solvent was removed from the solution at 240 ° C. under vacuum to obtain a triblock copolymer (A-) consisting of a lactone cyclized copolymer of butyl polyacrylate at the central block and MMA, RHMA and ST on both sides. 2) was obtained.
A-2 had a weight average molecular weight of 327,000, a number average molecular weight of 182,000, a molecular weight distribution of 1.8, a glass transition temperature of 122 ° C., and a thermal decomposition temperature of 319 ° C. Moreover, it was (circle) when the foamability evaluation of A-2 was implemented.

Example 2A: Block polymer synthesis and cyclization by nitroxide polymerization in the presence of a thiol compound As described below, polymerization and polymerization were performed in the same manner as in Example 2 except that polymerization was performed in the presence of a thiol compound. Cyclization was performed.

To a reactor equipped with a stirrer, temperature sensor, cooling tube, nitrogen inlet tube, 10 parts Flexibloc® D2, 10.8 parts methyl 2-hydroxymethyl acrylate (RHMA), 75.2 parts Methyl methacrylate (MMA), 2.3 parts of styrene (ST), n-dodecyl mercaptan (DM) 0.1 part, and 96.2 parts of toluene as a polymerization solvent were charged, and nitrogen was passed through the solution at 105 ° C. The temperature was raised to. Thereafter, solution polymerization was allowed to proceed for 3 hours under reflux at about 105 to 110 ° C. The reaction rate calculated from the amount of monomers in the polymerization solution at this time was 23% for MMA, 25% for RHMA, and 44% for ST. Furthermore, 0.1% of methanol was detected from the obtained polymerization solution. This supports the occurrence of intramolecular lactone cyclization accompanying transesterification with the polymerization reaction.
Next, the residual monomer and solvent were removed at 2.6 kPa and 80 ° C. for about 2 hours, and then 150 parts of toluene was added and dissolved uniformly, then charged in a pressure vessel made of SUS316 and replaced with a nitrogen atmosphere at 240 ° C., 2 And held at 5 MPa for 90 minutes. Thereafter, the solvent was removed from the solution at 240 ° C. under vacuum to obtain a triblock copolymer (A-) consisting of a lactone cyclized copolymer of butyl polyacrylate at the central block and MMA, RHMA and ST on both sides. 7) was obtained.
A-7 had a weight average molecular weight of 311,000, a number average molecular weight of 194,000, a molecular weight distribution of 1.6, a glass transition temperature of 122 ° C., and a thermal decomposition temperature of 332 ° C. Moreover, it was (circle) when the foamability evaluation of A-7 was implemented.

Comparative Example 1: Block Polymer Synthesis by Nitroxide Polymerization A reaction apparatus equipped with a stirrer, a temperature sensor, a condenser tube, and a nitrogen introduction tube was added to 58 parts of Flexibloc® D2, 105 parts of methyl methacrylate (MMA), and 40 parts of toluene was charged as a polymerization solvent, and the temperature was raised to 105 ° C. while introducing nitrogen into the solvent. Thereafter, solution polymerization was allowed to proceed for 3 hours under reflux at about 105 to 110 ° C. The reaction rate of MMA calculated from the amount of monomers in the polymerization solution at this time was 28%. Methanol was not detected from the polymerization solution (detection lower limit; 5 ppm or less). Thereafter, the solvent was removed from the solution at 240 ° C. under vacuum to obtain a triblock copolymer (A-3) in which the central block was polybutyl acrylate and the blocks on both sides were MMA.
A-3 has a weight average molecular weight of 192,000, a number average molecular weight of 121,000, a glass transition temperature of 107 ° C., and a thermal decomposition temperature of 264 ° C., confirming a gradual weight decrease and isothermal at 288 ° C. Degradation behavior was shown. Moreover, it was x when foaming evaluation of A-3 was carried out.

Example 3: Synthesis of block polymer by nitroxide polymerization and additional polymerization of unreacted monomer, simultaneous cyclization reaction 71 parts Flexibloc® D2, 96.9 parts methyl 2-hydroxymethyl acrylate (RHMA), 674 Solution polymerization proceeded for 1.5 hours under reflux as in Example 1 except that 5 parts methyl methacrylate (MMA), 20.4 parts styrene (ST) and 632 parts toluene as polymerization solvent were used. I let you. Since the reaction rate calculated from the amount of monomers in the polymerization solution at this time was 17% for MMA, 19% for RHMA, and 30% for ST, it was confirmed that block polymerization was proceeding. A part of this polymerization solution was extracted and heated under vacuum at 240 ° C. for 15 minutes, and the monomer and solvent were distilled off to obtain a block polymer (BP). When the molecular weight of the obtained block polymer was determined, the weight average molecular weight (Mw) was 328,000, the number average molecular weight was 175,000, and the molecular weight distribution was 1.9.
Next, 0.34 parts of n-dodecyl mercaptan and 0.81 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) were added to further react the remaining monomer. 5 minutes later, a liquid comprising 15.8 parts by mass of styrene, 5.6 parts of toluene, and 1.63 parts of a dropping initiator t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570). The solution was polymerized at 100 to 110 ° C. while dropping over a period of 2 hours, and further aged for 4 hours. The reaction rates calculated from the amount of monomers in the polymerization solution at this time were 91% for MMA, 91% for RHMA, and 99% for ST. From the obtained polymerization solution, 1.1% of methanol was detected to support that the lactone cyclization reaction proceeded quantitatively during the polymerization.
Subsequently, it was charged in a pressure vessel made of SUS316 and maintained at 240 ° C. and 2.5 MPa for 30 minutes while being replaced with a nitrogen atmosphere. Thereafter, the polymerization solution was diluted with methyl ethyl ketone (MEK) so that the polymer solid content concentration was 30% by mass, then the barrel temperature was 270 ° C., the rotation speed was 200 rpm, the degree of vacuum was 13.3 to 400 hPa (10 to 300 mmHg), and the rear vent number was 1. Introduced into a vent type twin screw extruder (φ = 15 mm, L / D = 30) with four fore vents (referred to as first, second, third and fourth vents from the upstream side) and devolatilization And a polymer composition (A-4) containing a triblock copolymer consisting of a lactone cyclized copolymer of MMA, RHMA, and ST on the center block and polybutyl acrylate on the central block was obtained.
A-4 had a weight average molecular weight of 179,000, a number average molecular weight of 70000, a molecular weight distribution of 2.6, a glass transition temperature of 122 ° C., and a thermal decomposition temperature of 334 ° C. Moreover, it was (circle) when the foamability evaluation of A-4 was implemented.

Example 4: Synthesis of block polymer by nitroxide polymerization and additional polymerization of unreacted monomer, simultaneous cyclization reaction 142 parts Flexibloc® D2, 91.8 parts methyl 2-hydroxymethyl acrylate (RHMA), 639 Parts of methyl methacrylate (MMA), 19.4 parts of styrene (ST) and 632 parts of toluene as polymerization solvent, and 0.34 parts of n-dodecyl mercaptan, t -0.81 part of amyl peroxy isononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) was added, and 5 minutes later, 15.0 parts by mass of styrene, 5.6 parts of toluene, addition initiator t- Amilperoxy isononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570) The lactone ring reaction is performed simultaneously with the polymerization in the same manner as in Example 3 except that the liquid consisting of 63 parts is dropped over 2 hours, and then devolatilization is performed so that the central block is polybutyl acrylate, the blocks on both sides are A polymer composition (A-5) containing a triblock copolymer composed of a lactone cyclized copolymer of MMA, RHMA and ST was obtained.
When the molecular weight of the block polymer obtained before the reaction of the remaining monomer was determined, the weight average molecular weight (Mw) was 285,000, the number average molecular weight was 15,000, and the molecular weight distribution was 1.8. Moreover, the weight average molecular weight of A-5 was 176,000, the number average molecular weight was 72,000, the molecular weight distribution was 2.4, the glass transition temperature was 121 ° C, and the thermal decomposition temperature was 335 ° C. Moreover, it was (circle) when the foamability evaluation of A-5 was implemented.

Example 5: Synthesis of block polymer by nitroxide polymerization and additional polymerization of unreacted monomer, simultaneous cyclization reaction 213 parts Flexibloc® D2, 86.7 parts methyl 2-hydroxymethyl acrylate (RHMA), 603 .5 parts methyl methacrylate (MMA), 18.3 parts styrene (ST) and 632 parts toluene as polymerization solvent, 0.34 parts n-dodecyl mercaptan, initiator for further reaction of the remaining monomers 0.81 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., Luperox (registered trademark) 570) was added, and after 5 minutes, 14.2 parts by mass of styrene, 5.6 parts of toluene, and a dropping initiator t-amyl peroxy isononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570) Except that a solution consisting of 1.63 parts is dropped over 2 hours, the lactone ring reaction is performed simultaneously with the polymerization in the same manner as in Example 3, and then devolatilization is performed, so that the central block is polybutyl acrylate, both sides A polymer composition (A-6) containing a triblock copolymer having a block made of a lactone cyclized copolymer of MMA, RHMA and ST was obtained.
When the molecular weight of the block polymer obtained before the reaction of the remaining monomer was determined, the weight average molecular weight (Mw) was 274,000, the number average molecular weight was 152,000, and the molecular weight distribution was 1.8. Moreover, the weight average molecular weight of A-6 was 172,000, the number average molecular weight was 65,000, the molecular weight distribution was 2.6, the glass transition temperature was 120 ° C, and the thermal decomposition temperature was 332 ° C. Moreover, it was (circle) when the foamability evaluation of A-6 was implemented.

  Table 1 shows the evaluation results of the polymers obtained in Examples 1 to 5 and Comparative Example 1.

As Example 1-5 and 2A show, the block copolymer excellent in heat resistance was able to be obtained easily by performing a lactone cyclization reaction also in a nitroxide polymerization process. Moreover, such a block copolymer had few foaming by heating.
On the other hand, the block copolymer of Comparative Example 1 having no lactone ring was inferior in heat resistance as compared with Examples 1 to 5 and 2A, and was much foamed by heating.
In addition, the block copolymers obtained in the examples have high thermal stability. In particular, as is clear from the results of Examples 2 and 2A, the addition of a thiol compound during polymerization further increases the thermal stability. It turned out that it becomes a polymer excellent in property.

Production Example 1: Synthesis of lactone cyclized polymer In a reaction apparatus equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, 40 parts of methyl methacrylate (MMA), 10 parts of methyl 2-hydroxymethyl acrylate ( RHMA), 50 parts of toluene as a polymerization solvent and 0.025 part of Adeka Stub 2112 (manufactured by ADEKA) as an antioxidant were charged, and the temperature was raised to 105 ° C. while passing nitrogen through the mixture. When refluxing with the temperature increase started, 0.05 parts of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi, Luperox (registered trademark) 570) was added as a polymerization initiator, and 0.10 parts of While t-amyl peroxyisononanoate was added dropwise over 2 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.
Next, 0.05 part of 2-ethylhexyl phosphate (“Phoslex A-18” manufactured by Sakai Chemical Industry Co., Ltd.) was added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction for forming a lactone ring structure was allowed to proceed for 2 hours under reflux at ˜110 ° C. Subsequently, the polymerization solution was passed through a multitubular heat exchanger heated to 240 ° C. to further advance the cyclization condensation reaction.
Next, the obtained polymerization solution was subjected to a barrel temperature of 280 ° C., a rotation speed of 120 rpm, a degree of vacuum of 133 to 800 hPa (100 to 600 mmHg), a rear vent number of 1 and a fore vent number of 4 (first, second, (Referred to as third and fourth vents), a side feeder is provided between the third vent and the fourth vent, and a leaf disk type polymer filter at the tip (filtration accuracy 5 μm, filtration area 0.5 m ² ) Was introduced into a vent type screw twin screw extruder (Φ = 50.0 mm, L / D = 53) at a processing speed of 31.2 parts / hour in terms of resin amount, and devolatilization was performed. At that time, 0.472 parts / hour of ion-exchanged water was added from behind the second vent at a charging rate of 0.162 parts / hour with a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator. Were fed from behind the first and third vents, respectively. In the mixed solution of antioxidant / cyclization catalyst deactivator, two parts of antioxidant (Irganox 1010 manufactured by Ciba Specialty Chemicals Co., Ltd., Adekastab AO-412S manufactured by Asahi Denka Kogyo Co., Ltd.) and A solution in which 3.4 parts of zinc octylate (manufactured by Nippon Kagaku Sangyo Co., Ltd., 3.6% of Nikka octix zinc) was dissolved in 30.4 parts of toluene was used. Further, pellets of a styrene-acrylonitrile polymer (the ratio of styrene / acrylonitrile was 73% by weight / 27% by weight and the weight average molecular weight 190,000) were charged from the side feeder at a rate of 3.22 parts / hour. The resin composition remaining in the extruder in the hot melt state is discharged while filtering through a polymer filter from the tip of the extruder, and after passing through the provided die, a filter having a pore diameter of 1 μm (product name: Micropore, manufactured by Organo Corporation). The strand is cooled by a water tank filled with cooling water filtered through a filter 1EU) and maintained at a temperature within a range of 30 ± 10 ° C., and introduced into a cutting machine (pelletizer), so that the lactone ring structure becomes a main chain. The pellet of the resin composition (B-1) containing the lactone ring system polymer which has and a styrene- acrylonitrile copolymer was obtained. B-1 had a weight average molecular weight of 135,000, a number average molecular weight of 50,000, a glass transition temperature of 125 ° C., and a thermal decomposition temperature of 340 ° C.

Production Example 2: Synthesis of lactone cyclized polymer In a reaction vessel equipped with a stirrer, a temperature sensor, a cooling pipe and a nitrogen introduction pipe, 229.6 parts of methyl methacrylate (MMA), methyl 2-hydroxymethyl acrylate (RHMA) 33 parts, 248.6 parts of toluene, and 0.19 parts of n-dodecyl mercaptan were charged, and the temperature was raised to 105 ° C. while introducing nitrogen into the mixture. When the reflux accompanying the temperature increase started, 0.20 parts of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Corp., Luperox (registered trademark) 570) was added as a polymerization initiator, and the above-mentioned t-amylperoxy While dripping 0.40 parts of isononanoate and 12.4 parts of styrene over 2 hours, the solution polymerization was allowed to proceed under a reflux of about 105 to 110 ° C., and after completion of the dropwise addition, aging was continued for 4 hours at the same temperature. Went.
Next, 0.21 part of stearyl phosphate (“Phoslex A-18” manufactured by Sakai Chemical Industry Co., Ltd.) as a catalyst for the cyclization condensation reaction (cyclization catalyst) is added to the obtained polymerization solution, and about 90 to 110 is added. The cyclization condensation reaction for forming a lactone ring structure was allowed to proceed for 2 hours under reflux at 0 ° C.
Next, the obtained polymerization solution was passed through a multitubular heat exchanger heated to 240 ° C. to complete the cyclization condensation reaction, and then the barrel temperature was 250 ° C., one rear vent, four Fore vent (referred to as the first, second, third and fourth vents from the upstream side) and a side feeder between the third vent and the fourth vent, and a leaf disk type polymer filter (filtration accuracy at the tip) 5 μm) was introduced into a vent type screw twin screw extruder (L / D = 52) at a processing speed of 31.2 parts / hour (resin amount conversion). At that time, ion-exchanged water was added from behind the second vent at a rate of 0.47 part / hour, and 0.66 part of an ultraviolet absorber (ADKKA "ADK STAB (registered trademark) LA-F70") was added to toluene. A solution dissolved in 1.23 parts is charged from behind the third vent at a charging rate of 0.59 parts / hour, and further ion exchange water is charged from behind the fourth vent at a charging rate of 0.47 parts / hour. I put it in.
After completion of devolatilization, the resin composition (B-2) containing a lactone ring polymer having a lactone ring structure in the main chain and an ultraviolet absorber (UV absorber) by pelletizing in the same manner as in Production Example 1. Pellets were obtained. B-2 had a weight average molecular weight of 13,000, a number average molecular weight of 60,000, a glass transition temperature of 122 ° C., and a thermal decomposition temperature of 335 ° C.

Examples 6-8
The polymers (A-4) to (A-6) containing the block polymers obtained in Examples 3 to 5 were melt-extruded at a temperature of about 260 to 270 ° C. with a vented single screw extruder having a T die, An unstretched film having a thickness of 160 μm was formed. The unstretched film was stretched 2 × 2 times using a corner stretch type biaxial stretching test apparatus (X6-S, manufactured by Toyo Seiki Co., Ltd.) to obtain a biaxially stretched film. Specifically, the distance between chucks when the cut film is set in a stretching test apparatus is set to 80 mm, the film attached to the chuck is preheated at the Tg + 23 ° C. for 3 minutes, and then the unstretched film at the temperature. The fixed end was biaxially stretched twice in the MD direction (flow direction) and then twice in the TD direction (direction perpendicular to the flow direction). The stretching speed was set to 300% / min, and heat stretching (annealing) was performed for 60 seconds after stretching. Table 2 shows the Tg, thickness, haze, folding resistance, and rate of change in internal haze before and after heating of each unstretched film.

Examples 9-11, Comparative Examples 2-4
The block polymers (A-1) to (A-3) and (A-7) obtained in Examples 1 and 2, Example 2A and Comparative Example 1 and the lactone ring structure obtained in Production Examples 1 and 2 are included. Resin compositions (B-1) to (B-2) were melt blended at a temperature of about 260 to 280 ° C. by a single-screw extruder with a vent having a T die after dry blending according to the blending ratio shown in Table 2. An unstretched film having a thickness of 160 μm was formed. Next, the film was stretched 2 × 2 times at Tg + 23 ° C. in the same manner as in Examples 6 to 8 to obtain a biaxially stretched film. Table 2 shows the Tg, thickness, haze, folding resistance, and rate of change in internal haze before and after heating of each unstretched film.

As shown in Examples 6 to 11, in stretched films comprising a polymer containing a block polymer having a lactone ring structure and a composition, Comparative Examples 3 and 4 containing no block polymer while maintaining high heat resistance and transparency. In contrast, a tough biaxially stretched film having excellent bending strength could be obtained. Since the block polymer itself has a ring structure and a high thermal decomposition temperature, no adverse effects such as foaming at the time of film formation were confirmed, and it was suitable for the melt film formation process.
In Comparative Example 2 using a polybutyl acrylate and a block polymer composed of MMA on both sides, it is thought to be caused by foaming that seems to be due to insufficient heat resistance of the film and poor compatibility between the lactone resin and the block polymer. Hazy (high turbidity) unevenness was observed.
It was also confirmed that when the molecular weight of the block polymer was relatively large, the rate of change in internal haze before and after heating was small and the thermal stability was excellent.

  According to the present invention, a lactone ring structure can be formed along with the formation of a polymer block containing an acrylate unit and a block polymer of a block containing a methacrylic ester unit and a 2-hydroxymethylacrylic acid monomer unit. A block copolymer having a polymer block containing a structural unit derived from an acrylate ester and a polymer block containing a structural unit derived from a lactone ring structure and a methacrylic acid ester can be efficiently produced.

Claims (10)

  A method for producing a block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylate ester, A polymerization step of polymerizing a nitroxide polymer (A1) having a nitroxide structure having an organophosphorus unit and a monomer (B1) containing a methacrylic acid ester and a 2-hydroxymethylacrylic acid monomer at the terminal of the block (A) The manufacturing method of a block copolymer.   The production method according to claim 1, wherein in the polymerization step, polymerization is performed in the presence of a thiol compound.   A block copolymer having a polymer block (A) containing a structural unit derived from an acrylate ester and a polymer block (B) containing a structural unit derived from a lactone ring structure and a methacrylic acid ester and having a weight average molecular weight of 150,000 or more. Polymer.   The block copolymer according to claim 3, wherein the molecular weight distribution is 3 or less.   The block copolymer according to claim 3 or 4, wherein the thermal decomposition temperature is 300 ° C or higher.   The film containing the block copolymer in any one of Claims 3-5.   The film according to claim 6, which is an optical film.   The film according to claim 6 or 7, which is a polarizer protective film.   A polarizing plate comprising the film according to claim 6.   An image display device comprising the polarizing plate according to claim 9.